An image forming apparatus, such as a printer or a multi-function printer, includes a system for performing an image forming process, which generally requires a significant amount of power consumption. Accordingly, when the image forming process is not being performed, the image forming apparatus is preferably in a sleep mode.
To that end, a conventional image forming apparatus may typically reduce the power consumption by preventing power from being supplied to various elements, such as an image forming unit, a scanning unit, an operating panel equipment (OPE), and/or the like, which are not typically necessarily to be operational during the sleep mode.
However, according to the conventional method, even when the image forming apparatus is in the sleep mode, power is still supplied to the main controller, i.e., a logic IC including an application specific integrated circuit (ASIC), a random access memory (RAM), and a read only memory (ROM) to, for example, monitor whether a printing command is transferred from a user or from a host computer through an interface, e.g., a USB interface.
The logic IC functioning the main controller typically requires several watts or more of power. It is thus desirable to further reduce the power consumption when the image forming apparatus is in the sleep mode.